This invention relates to a folding knife with at least two lockable folding blades, and, more particularly, to such a knife wherein the selection and opening of the blade to be used is accomplished easily with one hand.
Knives are commonly available with either fixed blades or extendable blades. The fixed blade knife, whose blade is permanently fixed in the extended position, is popular with outdoorsmen because it is strong and can be provided with features particularly useful in hunting, fishing, and other outdoor activities.
The extendable blade knife, on the other hand, can be provided with multiple blades and many more features than the fixed blade knife. The extendable blade knife is also more compact than the fixed blade knife for carrying and storage. The most popular type of extendable blade knife is the folding blade knife, and the present invention relates to such folding blade knives.
More particularly, it relates to such knives having at least two blades that are normally folded into the knife body, can be independently selected by the user, and then can be selectively rotated to an opened position for use.
The folding blade knife has a knife body and at least one pivot pin. The blades are pivotably mounted to the pivot pin or pivot pins. The knife usually has a retention mechanism to hold the blades in the closed position within the knife body, until the user of the knife selects one of the blades for use. The selected blade is controllably extended by rotating it about its pivot pin to the open position. The locking mechanism then locks the selected blade in the open position in a manner that permits later selective unlocking of the blade and rotating it back to the original closed position.
Although the folding knife has many advantages, existing models have shortcomings in some applications. As an example, the use of a folding knife having more than one blade typically requires the user to visually inspect the knife to find the blade to be used. Once the desired blade is identified, the user holds the knife body in one hand and grasps the sides of the blade in the other hand. The blade is pivoted about its pivot point from the closed to the open position in a circular motion with both hands. The knife and blade are then used in the desired manner, usually holding the knife body in only one hand.
At a later time, the user of the knife may see the need for the use of a different blade. To select and deploy a different blade, the user again grasps the body of the knife in one hand and the opened blade in the other, releases the open-position lock, and folds the blade to the closed position with the reverse of the opening movement. The user visually inspects the knife to find the other blade to be used, and repeats the opening procedure described above. For some knife designs, the user may have t: reverse the knife end-for-end to position the other blade for opening.
Each time the knife is used, the user of the knife must divert attention from the ultimate use of the knife to find the blade to be deployed. The user must employ both hands to open and close the knife. Since the ultimate holding of the knife usually requires only one hand, the user must release the grasp of any object in the other hand in order to open the knife or to change blades. And, in each case, the user must divert primary attention from the task at hand to the knife. For many knife applications, this sequence of events in the use of the knife and its shortcomings do not pose a problem. In other situations, it poses serious obstacles. To cite an example, when a law enforcement officer or emergency rescue worker seeks to rescue an injured person trapped in a vehicle, a conventional cutting blade may be used to cut away a portion of an article of clothing worn by the trapped person in order to gain access to the seat belt that holds the person in place. A specially adapted web cutting tool is then used to cut through the seat belt harness that holds the person in place. Both the conventional blade and the web cutting tool are conveniently provided in a folding knife.
The rescue is often accomplished in a confined space under highly adverse conditions such as near-total darkness. With a conventional folding knife, the user of the knife must divert attention from the person being rescued to the knife, and must release the grip on the person or seat belt being cut to close the conventional blade and open the web cutting tool. Within the confined space and in darkness, it may not be possible to see the knife to select the blade. These problems can result in confusion and the loss of time in the rescue. While this example highlights the problem, the same difficulties can arise in many other uses of folding knives.
Thus, there is a need for an improved knife that offers greater selectivity and control in managing the use of the knife, particularly in adverse circumstances. The present invention fulfills this need, and further provides related advantages.